Site-to-site variation in the factors affecting cesarean section rates.

OBJECTIVE

To investigate the influence of various factors, including physician specialty, on the risk of cesarean birth.

DESIGN

Retrospective medical chart review.

PARTICIPANTS

Review of 7367 deliveries at five hospitals in five different states.

MAIN OUTCOME MEASURE: Method of delivery.

RESULTS

Logistic regression modeling using clinical and demographic risk factors found that the risk factors that influence cesarean delivery varied considerably among different hospitals. Only primiparity (relative risk, 2.22 to 5.81 among sites) and multiple gestation (relative risk, 4.74 to 100.48 depending on the site) were associated with increased cesarean delivery in all sites. Private insurance, preeclampsia, and having an obstetrician as the primary medical provider were also independently associated with cesarean delivery in four sites. Examination of 50 other variables showed no consistent independent associations with cesarean delivery.

CONCLUSIONS

The clinical and nonclinical factors that influence cesarean section are highly site dependent. This implies that physicians practicing at different sites are influenced by different criteria when deciding whether a cesarean delivery should be performed.